Re: [Gimp-user] image alignment/registration

[Casey Connor <gimp-user-list caseyconnor org>]

> So, by looking at the help text, it seems that you used all the options suited
> to focus stacking.

At least in the help file I'm looking at, I think the only option "for" 
focus stacking is -m ? For lenses with focus breathing (i.e. almost all 
lenses) if you are changing the focus for each shot, that will have the 
effect of changing the FOV a little bit, and that option apparently 
enables correction for that effect. But it may also be useful if you 
happened to move forward/back a bit between shots (which isn't really 
the same as zooming, of course, but is similar). You could try not using 
-m and see if it makes a difference for your use.

-x -y and -z sound like they attempt to correct for moving around 
slightly when you take the picture (i.e. translational as opposed to 
rotational changes?)

-d sounds like it might compensate for distortion due to rotation (i.e. 
the distortion when you are close with a wide angle lens) but I'm just 
guessing. :-)

I think the lesson is that align_image_stack defaults to not applying 
most of the corrections, and if you want them, you have to enable them.

I wonder if --distortion would also be a smart thing to turn on.

-c